Zeolites are microporous crystalline alumosilicate materials with well-defined system of channels and cages.
Due to their specific structure and chemical composition they have large internal surface area, adsorption capacity as well as ion-exchange capacity. They are thermally stable and the level of their hydrophobicity is tunable.
Small-pore zeolites have pore openings comprising eight-membered rings.
They present excellent catalyitic activity in the synthesis of olefins from methanol (MTO), as well as in the elimination of various harmful gases, particularly nitrogen-containing exhaust gases. Within the proposed project, a series of small-pore zeolite materials (CHA-, LTA-, LEV-framework types) will be synthesized and subsequently ion-exchanged by copper which will generate the metal centers required for catalytic reactions leading to a reduction in the emission of harmful gases.
In order to prepare materials with improved properties, the synthesis of the material will be mechanochemically-assisted by the pre-treatment of the starting compounds. The mechanochemical treatment is also going to be applied during the ion-exchange with copper. The obtained samples will be thoroughly characterized and those that will show adequate (hydro) thermal stability; quantity of the structural defects; particles’ shape and size; type, strength and distribution of acid sites, as well as the type and distribution of the copper species are going to be tested as catalysts in the reactions of the gaseous nitrogen compounds removal.
Particular attention will be paid to the evaluation of catalytic activity of the prepared materials in the selective catalytic reduction of nitrogen oxides by ammonia and the selective catalytic oxidation of ammonia.
The results of the project are published:
- in scientific journals as scientific articles:
1) Palčić, Ana; Valtchev, Valentin, Analysis and control of acid sites in zeolites. Applied catalysis. A, General, 606 (2020), 117795, 32 doi:10.1016/j.apcata.2020.117795.
2) Palčić, Ana; Cleto Bruzzese, Paolo; Pyra, Kamila; Bertmer, Marko; Góra-Marek, Kinga; Poppitz, David; Pöppl, Andreas; Gläser, Roger; Jabłońska, Magdalena, Nanosized Cu-SSZ-13 and Its Application in NH3-SCR. Catalysts, 10 (2020), 5; 506, 21 doi:10.3390/catal10050506.
- in conference proceedings/books of abstracts:
1) Kopljar, Katarina; Ardila Fierro, Karen Janella; Krajnc, Andraž; Mazaj, Matjaž; Palčić, Ana, Distribution of Al sites in SSZ-13 zeolites. Proceedings of the 9th Croatian-Slovenian-Serbian Symposium on Zeolites / Nuić, Ivona ; Mazaj, Matjaž ; Daković, Aleksandra (ur.). Zagreb: Croatian Zeolite Association, Bijenička 54, 10000 Zagreb, Croatia, 2021. str. 18-21. (usmeno predavanje)
- as master theses:
Kopljar, Katarina, Sinteza i karakterizacija zeolita strukturnog tipa CHA. Diplomski rad, Kemijski odsjek, Prirodoslovno-matematički fakultet Sveučilišta u Zagrebu, 2021.
Devices aquired in the frame of the project:
UV-VIS spectrometer Thermo Evolution 350 with Praying Mantis accessory
IKA magnetic stirrer
ILS shaking incubator
KNF vacuum pump